adaptivetau: Tau-Leaping Stochastic Simulation

Implements adaptive tau leaping to approximate the
trajectory of a continuous-time stochastic process as
described by Cao et al. (2007) The Journal of Chemical Physics
<doi:10.1063/1.2745299>. This package is based upon work
supported by NSF DBI-0906041 and NIH K99-GM104158 to Philip
Johnson and NIH R01-AI049334 to Rustom
Antia.